Leonard: I'm not going to make a fake appointment with a psychiatrist. What would I say is wrong with me?
Koothrappali: Low self esteem.
Howard: Social anxiety.
Sheldon: Sexual insecurity.
Leonard: None of that is true.
Penny: Denial. See sweetie, the list goes on and on.

Gallo: I'm curious. Are you related to Dr. Beverly Hofstadter?
Leonard: She's my mother. Do you know her?
Gallo: Not personally, but I have read all of her books.
Leonard: Then you know her better than I do.
Gallo: Well I'm not so sure about that. But I can tell you I do not agree with her theories on child rearing at all.
Leonard: Really. Any chance you find them cold, cruel and unsuitable for Innocent little boys who just want to be happy?
Gallo: Well, I didn't want to say it...
Leonard: No, say it! Say it! Rent a plane, write it in the sky.

No need to. As soon as she flies into California air space, I'll feel a disturbance in the force.

Penny: Think we'll have time to visit your mom while we're there?
Leonard: Yes. We'll also have time to put my junk in a garlic press, but I'm not doing that either.

Sheldon: Aren't you afraid of being blinded?
Leonard: How would I be blinded?
Sheldon: At the end of the ceremony, all the students throw those pointy hats in the air. It's all pomp and circumstance until someone loses an eye.

Sheldon: [singing] The itsy bitsy spider is not an insect at all. Because it has eight legs and two body parts.
Leonard: That’s pretty cool, Sheldon.
Sheldon: Thank you. Do either of you know Beyonce? I’d love her to get behind it.

Wil Wheaton: Leonard, a moment ago, you were dead set against Penny resuming her acting career, but now you're all for it. Is it fair to say she played you like a violin?
Leonard: Yes it is, Wil.

Sheldon: Is that the attitude to helped you get Penny?
Leonard: No, but I don't have three years to make that gate feel sorry for me.

Sheldon: Play that funky music, white boy!
Leonard: I'm surprised you know that reference.
Sheldon: What reference?

Sheldon: Would you like to play a physics car game I invented called "I Can't Spy"? It's all the nail biting tension of "I Spy," but the added fun of sub-atomic particles and waves outside the visible spectrum.
Leonard: If it's half as much fun as "One Times Ten to the Fourth Bottles of Beer on the Wall," I'm in.

Penny: I mean, who even reads Scientific American.
Leonard: It's kind of a big deal.
Penny: If it's such a big deal, how come the biggest celebrity they could get for the cover is a molecule?

Leonard: And we weren't even watching TV! We were watching Netflix like the kids do!
Penny: Yeah! Is it a comedy? Is it a drama? Nobody knows!

TBBT Quotes

It's very simple. Scissors cuts paper, paper covers rock, rock crushes lizard, lizard poisons Spock, Spock smashes scissors, scissors decapitates lizard, lizard eats paper, paper disproves Spock, Spock vaporizes rock, and, as it always has, rock crushes scissors

Sheldon

Sheldon: Why do you have the Chinese character for "soup" tattooed on your right buttock?
Penny: It's not "soup," it's "courage."
Sheldon: No it isn't. But I suppose it does take courage to demonstrate that kind of commitment to soup.
Penny: How'd you see it? You said you wouldn't look.
Sheldon: Sorry. As I told you, the hero always peeks.